The use of shear connectors, which are often known as shear studs, is to create a solid, complete connection between two different materials. In bridge deck construction, building construction and similar types of applications, this connection is between concrete and steel.
Through his use of shear studs, the two materials are bound to each other, allowing them to resist twisting, bending, sagging or independent movement between the two. Instead, they obtain a stronger, more rigid and more durable form, resisting shear forces and working as a composite material that is stronger than either one on its own.
The Design
Shear connectors are very simple in design. An unthreaded shaft and a thicker, slightly rounded head comprise the entire weld stud. Typically constructed of mild steel or stainless steel, they are essential in ensuring the safety of any composite of concrete and steel in the construction industry.
The shear studs are attached to the steel structural elements through the use of drawn arc stud welding technology. As these are larger weld studs and drawn arc stud welding is used, a ferrule is also required. This ferrule serves to contain the molten pool and to shield the welding process, producing a complete, even weld even with extremely fast stud welding cycle speeds.
Specialized ferrules and shear connectors are available to weld on the inside and outside of angles. This is critical on bridge decks and in building construction. Using the correct shear connector and ferrule for these locations provides a solid weld not possible with the standard design.
All shear connectors used in construction are required to meet specific requirements based on the project and the shear force calculations. These requirements are stipulated by building codes and industry regulations with the AWS and ASHTO requirements most frequently used.